Salt (i.e., sodium chloride) has been used for many years to control the formation and accumulation of snow and ice on roads. The salt is typically pre-wetted or dissolved with water into an aqueous brine solution that is applied to the road surface using spinners and/or spray nozzles attached to snow plows and other snow/ice removal vehicles.
In brine solutions of sodium chloride dissolved in water, the brine becomes fully saturated when the salt concentration reaches about 23 wt. %. This lower the freezing point of the solution from 32° F. (0° C.) for pure water to −6° F. (−21° C.) for the fully saturated brine. During winter months in many northern regions, temperatures can fall below −6° F., reducing the effectiveness of sodium chloride brines in breaking up and preventing the formation of snow and ice on roads and bridges.
One approach to overcoming the low-temperature limits of sodium chloride brines is to also spread sand, gravel and other abrasives over the snow and ice to increase the coefficient of friction between the road and vehicle tires. Unfortunately, vehicle traffic tend to push these materials off the road surface quickly, requiring frequent reapplication. Also, vehicle tires can kick up these materials into car windshields and grilles, which can cause significant vehicle damage and even pose safety risks.
Thus, there is a desire for new de-icing and anti-icing compositions that can melt snow and ice at temperatures below the freezing point of a pure sodium chloride brine. This and other issues are addressed in the present application.